“Such a solid is sometimes called a Heronian tetrahedron or a perfect pyramid.”

“The four C-H bonds are directed towards the four corners of a tetrahedron, with carbon at its center and hydrogens at each vertex.”

“If each face is an equilateral triangle, the result is a regular tetrahedron, one of the five Platonic solids.”

“When all four corners of the tetrahedra are shared, the mineral is called a tectosilicate.”

“The silica tetrahedra may also form a sheet structure where three oxygen atoms of each tetrahedron are shared by adjacent tetrahedra.”

“For example, the convex hull of a 3D molecule is a convex polytope rather than a polygon, and it is tessellated by tetrahedra rather than triangles.”

“Meshes comprised of hexahedrons are easier to visualize than meshes comprised of tetrahedrons.”

“Volumes of solids such as prisms, pyramids, tetrahedrons, wedges, cylinders and truncated cones are calculated.”

“Water as a matter has a specific geometric form: it forms tetrahedrons, one of the five platonic bodies.”